Selection of a subgroup A avian leukosis virus [ALV(A)] envelope resistant to soluble ALV(A) surface glycoprotein

Virology. 2000 Aug 1;273(2):364-73. doi: 10.1006/viro.2000.0424.


The host developing resistance to retroviral infection is believed to be a major force in the evolution of multiple receptor usage by retroviruses. The avian leukosis-sarcoma virus (ALV) group of retroviruses provides a powerful system for studying the envelope-receptor interactions involved in retrovirus entry; different members of this group of closely related viruses use distinct cellular receptors. Analysis of the ALV envelope subgroups suggests that the different ALVs evolved from a common ancestor by mutations in the env gene. Cells and animals that express subgroup A ALV envelope glycoproteins are highly resistant to ALV(A) infection due to receptor interference. In this study, we tested whether expression of a soluble form of subgroup A surface glycoprotein (SU) would result in receptor interference and whether this interference would select for resistant viruses with altered receptor usage. Chicken cells expressing the secreted ALV(A) SU immunoadhesin SU(A)-rIgG, which contains the subgroup A SU domain fused to the constant region of a rabbit immunoglobulin (IgG) heavy chain, showed significant receptor interference. A variant virus resistant to SU(A)-rIgG receptor interference was obtained. This virus had a six-amino-acid deletion in the subgroup A hr1 that altered receptor usage. This approach may identify regions of SU that play a critical role in receptor specificity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alpharetrovirus
  • Amino Acid Sequence
  • Animals
  • Capsid
  • Capsid Proteins*
  • Cell Separation
  • Chickens
  • Cloning, Molecular
  • Enzyme-Linked Immunosorbent Assay
  • Flow Cytometry
  • Molecular Sequence Data
  • Rabbits
  • Receptors, IgG / metabolism
  • Retroviridae Proteins
  • Viral Core Proteins
  • Viral Envelope Proteins / metabolism*


  • Capsid Proteins
  • Receptors, IgG
  • Retroviridae Proteins
  • Viral Core Proteins
  • Viral Envelope Proteins
  • nucleocapsid protein, Avian retrovirus